How to Use BEC module : Examples, Pinouts, and Specs

A BEC (Battery Elimination Circuit) module is an electronic device designed to provide a regulated voltage output from a battery source. It eliminates the need for a separate battery to power servos, receivers, and other components in remote-controlled (RC) applications. By stepping down the voltage from the main battery, the BEC module ensures that sensitive electronics receive a stable and safe power supply.

• Powering RC receivers and servos in drones, cars, boats, and planes.
• Supplying regulated voltage to microcontrollers and sensors in robotics.
• Providing a stable power source for LED lighting systems in RC models.
• Reducing the weight of RC systems by eliminating the need for additional batteries.

Below are the general technical specifications for a typical BEC module. Note that specific values may vary depending on the model and manufacturer.

The BEC module typically has three main connections: input, output, and ground. Below is a table describing the pin configuration.

Some BEC modules may also include a jumper or switch to select the output voltage (e.g., 5V or 6V).

1. Connect the Input Voltage:

   • Connect the VIN (+) pin to the positive terminal of your battery.
   • Connect the GND pin to the negative terminal of your battery.

2. Connect the Output Voltage:

   • Connect the VOUT (+) pin to the positive power input of your load (e.g., RC receiver, servo, or microcontroller).
   • Ensure the GND pin is also connected to the ground of your load.

3. Voltage Selection (if applicable):

   • If your BEC module has a voltage selection jumper or switch, set it to the desired output voltage (e.g., 5V or 6V) before powering the circuit.

4. Power On:

   • Once all connections are secure, power on the battery. The BEC module will regulate the voltage and supply power to the connected load.

• Check Voltage Compatibility: Ensure the input voltage is within the specified range of the BEC module. Exceeding the maximum input voltage can damage the module.
• Current Rating: Verify that the connected load does not exceed the maximum output current rating of the BEC module.
• Heat Dissipation: If the BEC module becomes warm during operation, ensure proper ventilation or consider adding a heatsink.
• Polarity: Double-check all connections to avoid reverse polarity, which can damage the module and connected components.
• Noise Filtering: For sensitive applications, consider adding a capacitor across the output to reduce voltage ripple.

A BEC module can be used to power an Arduino UNO from a LiPo battery. Below is an example circuit and code.

1. Connect the VIN (+) pin of the BEC module to the positive terminal of a 3S LiPo battery (11.1V).
2. Connect the GND pin of the BEC module to the negative terminal of the battery.
3. Connect the VOUT (+) pin of the BEC module to the 5V pin of the Arduino UNO.
4. Connect the GND pin of the BEC module to the GND pin of the Arduino UNO.

// Example code to blink an LED connected to pin 13 of the Arduino UNO
// Ensure the BEC module is providing a stable 5V to the Arduino UNO.

void setup() {
  pinMode(13, OUTPUT); // Set pin 13 as an output
}

void loop() {
  digitalWrite(13, HIGH); // Turn the LED on
  delay(1000);            // Wait for 1 second
  digitalWrite(13, LOW);  // Turn the LED off
  delay(1000);            // Wait for 1 second
}

1. Can I use a BEC module with a 2S LiPo battery?

   • Yes, most BEC modules support input voltages as low as 6V, which is suitable for a 2S LiPo battery.

2. Can I power multiple devices with a single BEC module?

   • Yes, as long as the total current draw of all devices does not exceed the maximum output current rating of the BEC module.

3. What happens if I exceed the input voltage range?

   • Exceeding the input voltage range can damage the BEC module. Always ensure the input voltage is within the specified range.

4. Is it safe to use a BEC module with sensitive electronics?

   • Yes, BEC modules are designed to provide a stable and regulated output voltage. For added safety, you can use a capacitor to further reduce voltage ripple.

By following this documentation, you can effectively integrate a BEC module into your projects and ensure reliable operation.